delay_diff: Delay-difference (weekly)

In pdolder/MixFishSim: Mixed Fishery fleet dynamics simulation tool

Delay-difference (weekly)

Description

delay_diff implements a two-stage delay-difference model with a weekly time-step after Dichmont 2003. Given the starting biomass, overall mortality and recruitment it returns the biomass in wk+1.

Usage

delay_diff(
  K = 0.3,
  F = NULL,
  M = 0.2,
  wt = 1,
  wtm1 = 0.1,
  R = NULL,
  B = NULL,
  Bm1 = NULL,
  al = NULL,
  alm1 = NULL
)

Arguments

K	is a Numeric vector describing growth. Note: K is transformed to rho with \rho = exp{-K} for the model. estimate of instantaneous fishing mortality (obtained elsewhere, via find_f and baranov_f functions.
F	is the weekly fishing mortality rate.
M	is a Numeric vector of the instantaneous rate of natural mortality for the population
wt	is a Numeric vector of the weight of a fish when fully recruited
wtm1	is a Numeric vector of the weight of a fish before its recruited
R	is a Numeric vector of the annual recruitment for the population in numbers
B	is the biomass of the population during wk_{t}
Bm1	is a Numeric vector of the biomass of the population in the previous week wk_{t-1}
al	is a Numeric vector of the proportion of recruits to the fishery in wk_{t}
alm1	is a Numeric vector of the proportion of recruits to the fishery in wk_{t-1}

Value

Returns the biomass at the beginning of the following week, wk_{t+1}

Examples

delay_diff(K = 0.3, F = 0.2, M = 0.2, wt = 1, wtm1 = 0.1, R = 1e6, B = 1e5,
Bm1 = 1e4, al = 0.5, alm1 = 0.1)

pdolder/MixFishSim documentation built on Oct. 17, 2023, 4:25 p.m.